﻿#define _CRT_SECURE_NO_WARNINGS
#include"snake.h"

void SetPos(short x, short y)
{
	//获得标准输出设备的句柄
	HANDLE houtput = NULL;
	houtput = GetStdHandle(STD_OUTPUT_HANDLE);

	//定位光标的位置
	COORD pos = { x, y };
	SetConsoleCursorPosition(houtput, pos);
}
//打印环境界面
void WelcomeToGame()
{
	SetPos(40, 14);
	wprintf(L"欢迎来到贪吃蛇小游戏\n");
	SetPos(42, 20);
	system("pause");
	system("cls");
	SetPos(25, 14);
	wprintf(L"用 ↑. ↓ . ← . → 来控制蛇的移动，按F3加速，F4减速\n");
	SetPos(25, 15);
	wprintf(L"加速能够得到更高的分数\n");

	SetPos(42, 20);
	system("pause");
	system("cls");
}
//绘制地图
void CreateMap()
{
	//上
	int i = 0;
	for (i = 0; i < 29; i++)
	{
		wprintf(L"%lc", WALL);
	}
	//下
	SetPos(0, 26);
	for (i = 0; i < 29; i++)
	{
		wprintf(L"%lc",WALL);
	}
	//左
	for (i = 1; i <= 25; i++)
	{
		SetPos(0, i);
		wprintf(L"%lc", WALL);
	}

	//右
	for (i = 1; i <= 25; i++)
	{
		SetPos(56, i);
		wprintf(L"%lc", WALL);
	}
}

//创建蛇
void InitSnake(pSnake ps)
{
	int i = 0;
	pSnakeNode cur = NULL;
	for (i = 0; i < 5; i++)
	{
		cur=(pSnakeNode)malloc(sizeof(SnakeNode));
		if (cur == NULL)
		{
			perror("malloc");
			exit(1);
		}
		cur->next = NULL;
		cur->x = POS_X + 2 * i;
		cur->y = POS_Y;
		//头插插入
		if (ps->_pSnake == NULL)
		{
			ps->_pSnake = cur;
		}
		else
		{
			cur->next = ps->_pSnake;
			ps->_pSnake = cur;
		}
	}
	cur = ps->_pSnake;
	while (cur)
	{
		SetPos(cur->x, cur->y);
		wprintf(L"%lc", BODY);
		cur = cur->next;
	}
	//设置贪吃蛇属性
	ps->_dir = RIGHT;
	ps->_score = 0;
	ps->_food_weight = 10;
	ps->_sleep_time = 200;
	ps->_status = OK;

	
}

////4.创建食物
 void CreateFood(pSnake ps)
{
	 int x = 0;
	 int y = 0;
	 //生成x是2的倍数
	 //x:2-54
	 //y:1-25
again:
	 do 
	 {
		 x = rand() % 53 + 2;//2-52
		 y = rand() % 25 + 1;
	 } while (x % 2 != 0);

	 //x和y坐标不能和蛇的身体冲突
	 pSnakeNode cur = ps->_pSnake;
	 while (cur)
	 {
		 if (x == cur->x && y == cur->y)
		 {
			 goto again;
		 }
		 cur = cur->next;
	 }
	//创建食物节点
	 pSnakeNode pFood = (pSnakeNode)malloc(sizeof(SnakeNode));
	 if (pFood == NULL)
	 {
		 perror("malloc");
		 exit(1);
	 }
	 pFood->x = x;
	 pFood->y = y;
	 pFood->next = NULL;

	 SetPos(pFood->x, pFood->y);//定位到位置
	 wprintf(L"%lc", FOOD);

	 ps->_pFood = pFood;

	

}
void GameStart(pSnake ps)
{
	system("mode con cols=100lines=30");
	system("title 贪吃蛇");
	HANDLE houtput = GetStdHandle(STD_OUTPUT_HANDLE);
	//影藏光标操作
	CONSOLE_CURSOR_INFO CursorInfo;
	GetConsoleCursorInfo(houtput, &CursorInfo);//获取控制台光标信息
	CursorInfo.bVisible = false; //隐藏控制台光标
	SetConsoleCursorInfo(houtput, &CursorInfo);//设置控制台光标状态
	//1.打印环境界面2.功能介绍
	WelcomeToGame();
	//2.绘制地图
	CreateMap();
	//创建蛇
	InitSnake(ps);
	//4.创建食物
	CreateFood(ps);
}




#define KEY_PRESS(vk)  ((GetAsyncKeyState(vk)&1)?1:0)
//打印帮助信息
void PrintHelpInfo()
{
	
	SetPos(64, 15);
	wprintf(L"%ls",L"不能穿墙，不能咬到自己");
	SetPos(64, 16);
	wprintf(L"%ls", L"用↑.↓.←.→分别控制蛇的移动");
	SetPos(64, 17);
	wprintf(L"%ls", L"F3为加速，F4为减速");
	SetPos(64, 18);
	wprintf(L"%ls", L"ESC：退出游戏，space：暂停游戏");
	SetPos(64, 20);
	wprintf(L"%ls", L"韩步轩");
}
//暂停
void Pause()
{
	while (1)
	{
		Sleep(200);
		if (KEY_PRESS(VK_SPACE))
		{
			break;
		}
	}
}
// 判断下一个坐标是否是食物
int NextIsFood(pSnakeNode pn, pSnake ps)
{
	return  (ps->_pFood->x == pn->x && ps->_pFood->y == pn->y);
}
//吃食物
void EatFood(pSnakeNode pn, pSnake ps)
{
	//头插
	ps->_pFood->next = ps->_pSnake;
	ps->_pSnake = ps->_pFood;

	//释放食物这个指针
	free(pn);
	pn = NULL;

	pSnakeNode cur = ps->_pSnake;
	while (cur)
	{
		SetPos(cur->x, cur->y);
		wprintf(L"%lc", BODY);
		cur=cur->next;
	}
	ps->_score += ps->_food_weight;

	//重新创建食物
	CreateFood(ps);
}
//不吃食物
void NoFood(pSnakeNode pn, pSnake ps)
{
	pn->next = ps->_pSnake;
	ps->_pSnake = pn;

	pSnakeNode cur = ps->_pSnake;
	while (cur->next->next != NULL)
	{
		SetPos(cur->x, cur->y);
		wprintf(L"%lc", BODY);
		cur = cur->next;
	}

	//把最后一个节点打印成空格
	SetPos(cur->next->x, cur->next->y);
	printf("  ");

	//释放最后一个节点
	free(cur->next);

	//把倒数第二个节点的地址置为NULL

	cur->next = NULL;
}

//蛇移动
void SnakeMove(pSnake ps)
{
	//创建一个节点，表示蛇即将要到的下一个节点
	pSnakeNode pNextNode = (pSnakeNode)malloc(sizeof(SnakeNode));
	if (pNextNode == NULL)
	{
		perror("malloc");
		exit(1);
	}

	switch (ps->_dir)
	{
	case UP:
		pNextNode->x = ps->_pSnake->x;
		pNextNode->y = ps->_pSnake->y - 1;
		break;
	case DOWN:
		pNextNode->x = ps->_pSnake->x;
		pNextNode->y = ps->_pSnake->y + 1;
		break;
	case LEFT:
		pNextNode->x = ps->_pSnake->x - 2;
		pNextNode->y = ps->_pSnake->y;
		break;
	case RIGHT:
		pNextNode->x = ps->_pSnake->x + 2;
		pNextNode->y = ps->_pSnake->y;
		break;
	}
	//检测下一个坐标处是否是食物
	if (NextIsFood(pNextNode, ps))
	{
		EatFood(pNextNode, ps);
	}
	else
	{
		NoFood(pNextNode, ps);
	}
	
}


void GameRun(pSnake ps)
{
	//打印帮助信息
	PrintHelpInfo();
	do
	{
		//打印总分数和食物的分值
		SetPos(64, 10);
		printf("总分是:%d\n", ps->_score);
		SetPos(64, 11);
		printf("当前食物的分数:%2d\n", ps->_food_weight);

		if (KEY_PRESS(VK_UP) && ps->_dir != DOWN)
		{
			ps->_dir = UP;
		}
		else if (KEY_PRESS(VK_DOWN) && ps->_dir!=UP)
		{
			ps->_dir = DOWN;
		}
		else if (KEY_PRESS(VK_LEFT) && ps->_dir != RIGHT)
		{
			ps->_dir = LEFT;
		}
		else if(KEY_PRESS(VK_RIGHT) && ps->_dir !=LEFT)
		{
			ps->_dir = RIGHT;
		}
		else if(KEY_PRESS(VK_ESCAPE))
		{
			ps->_status = END_NORMAL;
		}
		else if (KEY_PRESS(VK_SPACE))
		{
			Pause();
		}
		else if (KEY_PRESS(VK_F3))
		{
			//加速
			if (ps->_sleep_time > 80)
			{
				ps->_sleep_time -= 30;
				ps->_food_weight += 2;
			}
		}
		else if (KEY_PRESS(VK_F4))
		{
			//减速
			if (ps->_food_weight > 2)
			{
				ps->_sleep_time += 30;
				ps->_food_weight -= 2;
			}
		}
		SnakeMove(ps);//蛇走一步的过程

		Sleep(ps->_sleep_time);
		
	} while (ps->_status = OK);
	
}




//检测蛇是否撞墙
void KillByWall(pSnake ps)
{
	if (ps->_pSnake->x == 0 || ps->_pSnake->x == 56 ||
		ps->_pSnake->y == 0 || ps->_pSnake->y == 26)
	{
		ps->_status = KILL_BY_WALL;
	}
}
//检测蛇是否撞到自己
void KillBySelf(pSnake ps)
{
	pSnakeNode cur = ps->_pSnake->next;
	while (cur)
	{
		if (cur->x == ps->_pSnake->x && cur->y == ps->_pSnake->y)
		{
			ps->_status = KILL_BY_SELF;
			break;
		}
		cur = cur->next;
	}
}


void GameEnd(pSnake ps)
{
	SetPos(24, 12);
	switch (ps->_status)
	{
	case END_NORMAL:
		wprintf(L"您主动结束游戏\n");
		break;
	case KILL_BY_WALL:
		wprintf(L"您撞到墙上，游戏结束\n");
		break;
	case KILL_BY_SELF:
		wprintf(L"您撞到了自己，游戏结束\n");
		break;
	}
	
	//释放蛇身的链表

	pSnakeNode cur = ps->_pSnake;
	while (cur)
	{
		pSnakeNode del = cur;
		cur = cur->next;
		free(del);
	}
}
